The Cycle Stability and Rate Performance of LiNi0.8Mn0.1Co0.1O2 Enhanced by Mg Doping and LiFePO4 Coating

Abstract Nickel‐rich layered oxide LiNi 0.8 Mn 0.1 Co 0.1 O 2 became one of the preferred cathode materials for lithium‐ion batteries because of its advantages in capacity, cost and environmental protection. However, increased nickel content inevitably leads to more serious structural deterioration, such as irreversible phase transition, unexpected side effects as well as Li + /Ni 2+ mixing, etc. This results in poor cycle stability and rate performance. Herein, we proposed a co‐modification strategy for Mg doping and LiFePO 4 coating to enhance the aforementioned electrochemical performance of LiNi 0.8 Co 0.1 Mn 0.1 O 2 . The results indicated that Mg 0.02 ‐NCM@20LFP exhibited lower surface film resistance and charge transfer resistance than pristine material after 200 cycles at 1C. A cycle retention rate of 90.8 % can still be maintained after 100 cycles at 0.2C. When returning to 0.1C after 5C high magnification, 98 % of the capacity can be recovered, showing that the material has good structural integrity.